Field of the Invention
The present invention relates to an image processing apparatus that performs processing on an image and an image processing method as well as a storage medium that stores a program for causing a computer to execute the image processing method.
Description of the Related Art
Technologies of an object recognition from an image, an object detection, an orientation estimation, and the like have been widely used up to now, and various proposals have been made. These technologies are realized while a characteristic amount is generally extracted from an image to perform an identification. PCT Japanese Translation Patent Publication No. 2011-508325 discloses a technology as one effective method in terms of both an accuracy and a speed among various methods for characteristic amount calculation and identification. PCT Japanese Translation Patent Publication No. 2011-508325 discloses that a combination of predetermined characteristic point pairs is extracted from an image, respective pixel values thereof are obtained, and the pixel values are compared with each other in the respective characteristic point pairs to generate a characteristic amount. In addition, PCT Japanese Translation Patent Publication No. 2011-508325 discloses that the object detection is performed with respect to this characteristic amount by using an identifier of a cascade structure or a tree-type structure.
According to the technology disclosed in PCT Japanese Translation Patent Publication No. 2011-508325 where the identification is performed by the comparison between the respective characteristic points, since only a variation between the characteristic points is used, noise is contained in the respective characteristic points in an image containing large noise, which may be a cause of an accuracy degradation in image processing.